Scientists learn why scary soundtracks are scary

Yes, there was a certain something about that haunting soundtrack that really freaked out me--and the rest of the United States--watching the movie "Jaws" the first time. (It wasn't happenstance that beaches across the United States also reported lighter-than-usual traffic that summer of 1975.)

Roy Scheider (center) starred with Robert Shaw and Richard Dreyfuss in the blockbuster "Jaws."
Universal Pictures

Turns out that a film score like the one Steven Spielberg incorporated for his blockbuster movie actually mimic animal cries, or what scientists term "nonlinear vocalizations," according to a study just published in the journal Biology Letters.

"By their very nature, vocalizations containing nonlinearities may sound harsh and are somewhat unpredictable," the study found.

The researchers tested whether film soundtracks could evoke similar emotions in a range of film genres. They came up with the perhaps unsurprising conclusion that Hollywood filmmakers since D.W. Griffith have known: Sound tracks can manipulate human emotions.

Among other findings:

Dramatic films suppressed noise of all types, featuring more abrupt frequency transitions and musical sidebands. They also included fewer noisy screams than expected.

Horror films suppressed abrupt frequency transitions and musical sidebands. The also featured more non-musical sidebands, and noisy screams than anticipated.